Hi, I just picked an l3600dt 3 months ago. It is starting to get cold here and it's hard to start. The glow plug light never comes on. I'm new to tractors, but I am a certified auto tech. Where do I start with diagnosis? Where is the controller and relay located? I need to get this fixed before snow flys. Thank you.
L3600dt glow plug not working
- Thread starter Pikey
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85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
how does the key activate the glow plugs? Do you turn it ccw and hold? OR do you hold it past the run position? Not sure on your machine what the glow plug engage is like.
According to the manual it is supposed to turn on when the key is in the on position. It's a 3 position switch. Off, on, start
85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
See if this helps:
the light could be burned out.....test this with ohm meter
the wiring to GP could be at fault. see if 12+ volts are getting to top of plugs
YOU could have a bad GP too. Easy to test with Ohm meter, must remove connection at top, should be lower than 10 ohms, more like 1 ohm!!!
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If the glow plug was burned out would the light still illuminate, just never turn off? I honestly don't know. I'll pull the dashboard apart tonight and check the bulb. I would think that if the light is burned out the glow plug would still work. But, I've tried leaving the key in the on position for a few minutes and I never hear a relay click off and it is still hard to start below 60 degrees. From what I've been able to find, the relay is inside the dash panel. I'll start digging around with my multi meter. Hopefully I will be able to find out if it's the signal wire going to the relay that is bad, the relay, or the glow plug while I'm poking around
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Hi. I checked the glow plugs. They had a resistance of 1.5 ohms each. The bulb is good. I found the controller, relay, and timer. Any suggestions on how to figure out which one is bad? I don't Mind buying the controller and the relay as one is $57 and the other $27. But, the timer is $90! It looks like someone replaced the controller previously, as it was not mounted. It was just laying behind the cluster. Thanks again for your help on this.
it's almost always the controller. i've replaced 10:1 ratio on the controller vs relay.
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I'll grab a controller tomorrow. If that doesn't fix it I'll get a relay. At least my kubota dealer is only 15 minutes away
I replaced the controller and the light now illuminates.but it only stays on for 2 seconds. It is currently 55 degrees at my home. Should it stay on longer than that? If I disconnect the coolant temp sensor at the thermostat it stays on for approximately 12 seconds. They stay on a lot longer on a ford pickup
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85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Does it start after 2 seconds? IF so - you are golden.....if not - then you might be working on another sensor or something.
My B7100 need a glow even on 90 d days!!! Not long but it needs it!
Nope. It will not start. If I pull the temp sensor connection then it will start after the plugs run longer. I ran all tests that the dealer gave me and they all point to a bad controller. I checked the temp sensor and it speced fine
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I am also working on a glow plug issue: Does anyone know what the controller, timer, and relay are supposed to do? I replaced my relay and didn't change the problem with the light coming on but not going off. Not sure what the timer vs controller roles are?
yes at 55 you should get about 5-6 seconds of glow indicator at a minimum. i suspect the coolant temp plug wire loose somewhere or it has some corrosion on the temp sensor itself or threads where it goes into the block. i'd try to clean it up and wire brush the threads and check ohms with it outside the tractor using my house refrigerator to cool it to 34-36 degrees to check cold ohms and then a cup of hot water nearly boiling to check hot ohms and see if the sensor is good. i have a engine torn down now so i have a sensor in hand i can send you ohm readings on if needed.
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glow relay just allows voltage to go to the glow plug hot wire, the controller tell the relay when to come on and off as well as controlling the indicator light on the dash. controller determines engine temp via water temp in block or water jacket depending on your model. the relay is very simple design, the controller is a finicky delicate flower lol and is almost always the culprit for a glow light staying on all the time, blinking, or not on at all.
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I have the specs for the coolant temp sensor. Looking at parts available there are two of them. One that goes into the thermostat housing and another one with a single lead to it. I wonder which one is the issue. Note: disconnecting the one at the thermostat makes the glow plugs light for 8+ seconds. I did find in the manual that factory spec for my plug is .5 ohms. I'm getting 1.5 ohms
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disconnect one at a time and watch the temp sensor on the dash. that will tell you which one is not the dash coolant temp sensor and thus the other temp sender
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rbargeron
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L5450, L48, L3250, L345 never enough attachments
With the posts above it sounds like you are on the way to fixing it. A few years back I had a similar issue and found good ideas in this TBN thread on the same subject. Good luck, Dick B